The Plebeians being eliminated form Elysia didn't kill the faction. When Zakalawe left the new Elysian FM did a 180 with Elysia, turning them from xenophobic isolationists to 'They joined Yamatai' and we never heard from them sense.
This is also pretty much the trend everywhere: Bad FMs run the faction into the ground. They don't want anyone else to touch their stuff, they don't RP, and they are toxic to new players. People get driven away from these factions (or from the site all together).
As it stands right now, Nepleslia is a faction on death's door. The previous FMs have been copying War-hammer 40k as much as legally possible, much of Nepleslia's gear is from an earlier version of SARP's rules, and a lot of stuff doesn't really fit the setting.
But, if you're looking to change things around a new ID-Sol is as good a starting point as any. It does seem to make sense that it would be an upgrade program rather than a fresh-new body people could ST into. It also makes sense to have this be a body designed with using a power armor in mind. You've also got plenty of things to tie this into such as the decline of the Nepleslian empire, governmental instability, and 90's 'the streets are dangerous' gang fighting that Nepleslia is known for.
You could easily make this an event, and make it a good one, but you have to be willing to do something to the faction.